Department of Motor Vehicle laws in every state require that you pass a vision test to get or renew a driver’s license. While state laws may vary slightly, they typically call for visual acuity of at least 20/40 in either or both eyes, with or without corrective eyeglasses, and peripheral vision of 140 degrees.
Driver’s license vision screening focuses on visual acuity, peripheral vision and in some states, the ability to see colors. Check the laws in your state, as colorblindness may result in an automatic failure in some states. Examiners use a Snellen eye chart to measure visual acuity -- distance vision -- and a computerized machine to test peripheral vision. If you normally wear corrective lenses, bring them with you, as you must wear them during the exam.
Get an eye exam from a qualified eye care professional, such as a board-certified ophthalmologist or optometrist before or instead of taking a vision test at your local DMV. If you’re renewing an existing license, your state may be able to provide your doctor with a form to fill out to prove you meet the vision requirements for your state. This is especially important if you haven’t had a professional eye exam within the past year and may have issues that require correction.
Forgetting to blink and squeezing your eyes are common problems during a vision-screening test. Staring at a DMV eye chart without blinking increases tension around your eyes, which reduces vision and leads causes eye strain. Blinking also increases eye lubrication, which can significantly improve your ability to see clearly. According to Dr. Edward Kondrot, a board certified ophthalmologist and homeopathic physician, the keys are to blink lightly and often and do not squeeze either eye shut during the test.
Keeping your body hydrated helps prevent lack of tear production. When your eyes stop producing tears, dry eye, eyestrain and vision problems often follow. Dr. Kondrot recommends that you drink at least half your body weight in ounces of water each day. For example, if you weigh 120 pounds, drink 60 ounces of water each day. Start at least one week in advance, as this tactic won’t work if you wait until the day of the vision test.